Canon NP6251 Service Manual page 50

CHAPTER 2 BASIC OPERATION
Period
INTR From when the Copy
(initial Start key is pressed to
rotation) when CNTR1 starts.
CNTR1 For about 5 sec after
(control the end of INTR.
rotation 1)
CNTR2 For about 5 sec after
(control the end of CNTR1.
rotation 2)
AER From when the
(AE rotation) scanner has moved
forward about 120 mm
to when it returns to
home position.
SCFW While the scanner is
(scanner moving forward:
forward) • The distance the
scanner travels
forward varies
according to copy
paper size and ratio.
• The speed at which
the scanner travels
forward varies
according to ratio.
SCRV While the scanner is
(scanner moving in reverse.
reverse)
LSTR From the end of
(last SCRV to when the
rotation) main motor stops.
2-8
COPYRIGHT © 1997 CANON INC.
Function
Stabilizes the sensitivity
of the drum in
preparation for copying.
Controls the drum
surface potential VD.
Controls the drum
surface potential VL.
Measures the density of
the original while the
scanner is moving in
reverse.
The scanning lamp
illuminates the original,
and the reflected optical
image is projected to
the photosensitive drum
through mirrors and
lenses.
• Returns the scanner
to home position in
preparation for next
copying.
Rids the surface of the
drum of charges as post
treatment.
Table 2-102
CANON NP6350/NP6251 REV.0 JULY 1997 PRINTED IN JAPAN (IMPRIME AU JAPON)
Remarks
• Executed when mov-
ing the lens. If the
lens fails to reach a
specific position within
a specific period of
time, INTR is contin-
ued until the lens is
correctly positioned.
Before executing poten-
tial control, the scanner
motor is rotated in
reverse to return the
scanner to home posi-
tion without fail.
Determines the value of
the developing bias (DC
component) for copying
according to the
measurement of V .
L2
• Executed only in AE
mode.
• The registration signal
is generated to move
the copy paper to the
transfer assembly.
• The pick-up signal is
generated to pick-up
the second sheet.
Discharges the last
sheet.